The book itself is a jack-o-lantern. It is die cut to the pumpkin outline, stem and all, so a one year old picks it up and knows what it is before a single page turns. Inside, Lowly Worm and Huckle Cat drive Busytown's Halloween traffic: candy racers, a scarecrow car, and the sort of vehicle only Richard Scarry would think to build out of a wrapped sweet.

Everything about the object is sized for the smallest hands in the house. Under four inches square, thick chunky board throughout, twenty two pages, and no corner sharp enough to worry about. It fits in a coat pocket, a diaper bag or the top of a trick or treat pail, which is where a lot of these end up on the way home.

Penguin Random House lists it as a national bestseller. Scarry's vehicles have been the reason toddlers sit still for a book since the 1960s, and this is that machinery pointed at the one night of the year they are already excited about. Put it out with the decorations at the start of October and it becomes the book that means Halloween.